Problem with appearance of S-Log3 shots in Première Pro

[Rombau]

Hello, I got a project with rushes shot with an FX3 and an FX6. All shots were shot in S-Log3.

My problem is the following: once imported to Première Pro, an automatic LUT is applied to the FX6 shots while the FX3 shots appear well with the flat aspect of S-Log3.

However, I checked carefully, no input LUT is applied in lumetri, nor any look in the creative tab.

I have worked with this filming setup several times before and never had a problem. I feel like it's since I downloaded the Catalyst Browse app. Do you know if the Sony application can have an influence on the rushes imported into Première? I would like to point out that the rushes from the FX3 but also from the FX6 have the flat appearance of S-Log3 in Catalyst Browse.

What can I do to restore the appearance of S-Log3 from FX6 rushes in Première Pro please?

Thank you for your attention.

[R Neil Haugen]

Sony ... like many manufacturers, unfortunately ... seems to make the "same" format a bit different for each camera. Hence an "Xlog-Wx3" from one model may work as expected, but the "same" menu choice from another model from the same maker won't.

I've tested some supposedly identical Slog-3 files from a few different cameras, and one ... might have been the Fx3 ... was a bit different.

So in general, the Auto detect log and auto tonemapping in Premiere should be on (unless you know exactly what you're doing and why to go manual!) and that fixes most media now.

There are some Sony and Panny "log" settings that actually aren't log, they only "look log-ish". In other words, the camera settings when using that setting produce a standard encoding image file that is flat and low in saturation. Which might be the case here.

The Adobe tonemapping when it works, is actually a very good way technically to normalize log media into Rec.709 or HLG workflows. It isn't a 'final' Look, just a starter like any normalization LUT, but ... safer on the pixels than most LUTs.

[Rombau]

I am making a clarification because I think I expressed myself poorly.

My initial project contains rushes from FX6 and FX3 and were all shot in S-Log3. I did a large part of the editing by mixing the two sources and I have no problem. All the shots had the flat appearance of S-Log3. Except that one day, I restarted Adobe Premiere and there, it was as if all the shots shot with the FX6 already had an integrated LUT, which created a big difference in rendering with the shots from the FX3. I even had to delete the temporary calibration that I had applied myself.

I'm not sure but I think this problem appeared right after I installed the Catalyst Browse app and I think that's the problem. And since then I haven't been able to get the Flat appearance of the shots shot by the FX6 on Première Pro.

Is there a setting that I don't know about on Catalyst Browse or Première Pro to restore the original appearance?

Thanks in advance.

[R Neil Haugen]

I work for/with/teach pro colorists.  Who were the team that Dolby hired to create the DolbyVision HDR tutorials for Resolve users doing DoVi HDR for broadcast/streaming. I'm in Resolve daily, I've been around these processes over a decade. So I've got a little background in normalization.

If ... for some reason, you want the log un-normalized in Premiere, make sure that auto tonemapping is OFF. That is the only internal thing Premiere can or would do.

For the vast majority of log users, the better options in Premiere now for normalization is the auto detect log and auto tonemapping set to on. Skipping the LUT process completely. This is the safest way to get the pixels into Rec.709. 

Does it look a little different than a manufactureru's LUT you've used? Yea, of course. But there is not any "magic perfect LUT!" ... every normalization LUT is a combination of technical planning and also aesthetic choices. And while they can be built to handle a certain range of exposure and light quality of a scene ... well, they have limits where they simply bonk the data. Period.

Nearly all the colorists I work with build their own after studying manufacturer LUTs. Having learned the trade from them, I can go into LutCalc (on a Mac, you'd use Lattice of course) and build LUTs with soft rolloffs top & bottom et al, but no one can design a LUT that works perfectly for everything you'd shoot in the field. So having several for specific things per camera is pretty common.

And they really, really need to be the second thing applied, so you can go before the LUT to 'trim' exposure and sat, maybe even WB, before the LUT is applied, to get best, consistent application of the LUT to the clip.

And of course, no manufacturer even expects that any of their selection of normalization LUTs is anything other than the first step in processing the image into usable for a project. It's a preporatory thing, and they expect the user will modify the image further for every specific use. 

Premiere uses tonemapping algorithms for the log media it is now built to recognize.  In general tonemapping algorithms are a vastly superior method for normalizing than using LUTs. As they can have entire series of complex if then/this decisions as internal to the processing, which of course, no look-up table based process can. They are absolutely safer to the pixels than any LUT based normalization.

Like normalization LUTs, they are not "the final" image ... they are a prep step. And in general, the algorithms used in Premiere have been better than the LUTs I used to use. And I'm one that tended to deconstruct a manufacturer LUT, and then roll my own.

But we all differ. And your shop may have a long-set process that is built on certain normalization LUTs that is easier to just keep doing, even if a new method might be better. But you'd have to redo your shop process, and I recognize that ain't an easy thing to do in most places. Humans being well, human, right?

To do totally manual log normalization

.... turn off the auto-tonemapping option. You may also need to turn off auto detect log.

Between those, you should get LOG looking images back.

Now ... using the auto-detect log and auto tonemapping combined has another result ... you can use the same clip 'reference instance' in the bin for use in both SDR and HDR sequences.

With manual log work, if you have both SDR (Rec.709) and HDR sequences using the same clips, you need to create a duplicate clip in the bin, best adding the color space to the name. Use one for the SDR, the other for the HDR, so Premiere keeps the metadata straight.

[Kevin-Monahan]

Moving to Discussions for troubleshooting.